The present invention relates to tilting platform carriers in which the platform also slides in relation to the vehicle frame. These carriers are most often used to pick up and carry disabled vehicles transporting them to repair centers; they may also be used to transport industrial and agricultural equipment.
The basic motion of the platform relative to the truck frame is well illustrated in U.S. Pat. No. 3,485,400 of Pewthers. FIGS. 1-3 show the sequence of starting with the platform in a horizontal forward transporting position, to sliding the platform rearward, and finally raising the front of the platform with a hydraulic cylinder pivoting its distal overhanging end to ground contact. While these basic moves do not equate to modern carriers with additional disabled vehicle handling equipment, other patents in the prior art do relate to them.
Examples of patents relating to carriers of the present invention include the following: the Car Carrier of Lapiolahti (U.S. Pat. No. 4,750,856), Disabled Car Carrier Vehicle of Moore et al. (U.S. Pat. No. 4,756,658), Vehicle Carrier With Wheel Lift of Nespor (U.S. Pat. No. 5,061,147), and Wrecker Truck With Sliding Deck of Pinkston (U.S. Pat. No. 5,871,328). None of these prior art patents relate specifically to the objective of lowering the platform height.
The patent of Jaeger et al. entitled Low Center Of Gravity Carrier (U.S. Pat. No. 8,348,586) does meet this objective by moving the sub frame rails (which support the tilting platform and permit its sliding action) from above the vehicle frame rails sideways to between the chassis frame rails and the rear wheels. The bottoms of these sub frame rails are also moved down below the top surface of the adjacent chassis frame to reduce platform height.
The prior art does not reveal a carrier with sub frame rails above the carrier chassis frame rails that also reduces platform height thereby offering the associated advantages of lower center of gravity for better dynamic road handling, shallower load angle, and an increase in maximum payload height.